Mixing apparatus

ABSTRACT

The invention provides mixing apparatus which has a container base and a container lid with the lid carrying mixing means extending through the lid with at one end a mixing element and at the other end a drive connection to a drive motor. When the drive is operated the mixing element mixes the contents of the container, usually when the container inverted. The lid has a rim portion with a circumferential slot and the top edge of the container is located into the slot when the lid is assembled with the container whereby to improve connection between the lid and the container during mixing. The lid within the rim portion carries the mixing means and, during mixing, the assembly is held to lock the assembly together.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.10/566,974, filed Mar. 1, 2006, now U.S. Pat. No. 7,938,574 , which isthe U.S. national phase of International PCT Application No.PCT/GB2004/003432, filed Aug. 9, 2004, which designated the UnitedStates. PCT/GB2004/003432 claims priority of Great Britain PatentApplication No. 0318584.0, filed Aug. 7, 2003. The entire contents ofeach of these applications are herein incorporated by reference.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

This invention relates to mixing apparatus and, in particular, to mixingapparatus whereby food product can be mixed prior to consumption.

It has been proposed to provide mixing apparatus, more particularlyblending apparatus, in which a container of product fitted with a lid isblended by blending apparatus within the container.

The present invention is intended to provide improved apparatus formixing food products and which is specially adapted to be cost effectiveand sufficient for one trip use.

According to the invention there is provided mixing apparatus comprisinga container base and a container lid, the container lid having mountedthereon mixing means, the mixing means extending through the lid andhaving, at one end, means for connection to a drive motor external tothe container and, at the other end, a mixing element for mixing thecontents of the container when the drive means is operated, the mixingmeans comprising a shaft portion locatable through an opening in the lidand incorporating the connection means, and a mixing element portionassociated with the shaft portion for rotation therewith, the containerlid comprising a rim portion defining a circumferential slot into whichthe top edge of the container is located when the lid and container areassembled.

Preferably the container lid rim portion is formed with successive,oppositely-directed circumferential portions, one of the portions lyingclosely adjacent to the inner side wall of the container when the lidand container are assembled, and defining one side of the slot, andextending into the container.

Conveniently the other of the circumferential portions is spacedinwardly of the side wall and has a curvilinear join with the oneportion.

In one arrangement the circumferential slot is defined by an outerportion arranged to extend around the outer top edge of the container,and an inner portion arranged to extend into the container and the innerportion extends over a greater distance than the outer portion in theaxial direction of the container, such distance being between twice andsix times the distance.

In one arrangement, the mixing element portion includes an openingthrough which the shaft portion is located to lock into the opening.

The mixing means is assembled on to the lid, the shaft portion beingfirst inserted through one end of the lid opening, and then the mixingelement portion is locked onto the shaft portion at the opposite end ofthe shaft.

It is also possible to have one piece mixing means which is assembledwith the lid as one piece.

Preferably the mixing portion clips onto the shaft portion and issecured thereto by shoulder means on the shaft portion. The mixing andshaft portions may be united by welding them together.

The apparatus may comprise a support for an assembled container and lidwith the lid located on the support, and a clamping member movable toengage the end of the container opposite the lid and locate the assemblyduring operation of the mixing means in which the clamping member isreciprocally movable and, upon contacting the container to clamp theassembly, applies a predetermined force to the container in thedirection towards the support.

In one arrangement the clamping member is connected to a fixed memberthrough spring means and, upon the clamping force exceeding apredetermined level, the spring means compresses and a signal isgenerated to stop movement of the clamping member. In such arrangementthe clamping member may include a clamping surface engageable with thecontainer and extending beyond the side edges of the container andcomprising switch means for detecting an obstruction to a clampingaction.

Conveniently, the container lid is nestable or stackable with othercontainer lids, one being located inside the other.

Container lids assembled with the mixing means are also, preferably,arranged to be stackable or nestable.

Lubrication and/or cooling means may be provided to permit the contentsof the container, during mixing, to contact and lubricate and/or coolthe co-operating surfaces of the shank portion and the opening into thelid. Such lubricating means may include longitudinal slots in the sidewalls of the opening which constitute a sleeve.

A container lid may include a product access opening with closure meansso that, after completing a mixing operation, the opening is openable toaccess the contents.

The container lid may include holding means for holding product arrangedto be mixed with the material in the container before, during or afteroperation of the mixing means. The holding means may include a pockethaving an opening for introducing the product into the pocket.

The pocket may have mesh means for permitting product in the containerto enter into the pocket.

The pocket may be arranged to contain carbonation means for carbonatingproduct in the container. Alternatively or in addition the pocket maycontain flavour or other additives for the product.

According to another aspect, a blending lid for a container includes abody configured to be fitted over the open end of a container forsealing ingredients within the container, wherein the body has mountedthereon blending means arranged for a high speed rotation. The blendingmeans extends through an opening in the lid and has, at one end, meansfor connection to a drive motor external to the lid and, at the otherend, a blending element for blending contents of the container when thedrive means is operated. The blending lid is configured for stackingwith other blending lids of the same type and configuration, one on topof another, when the blending means is mounted on the body.

The body may include an upper portion in which the opening is formed,wherein the upper portion may include a recess which is annular to theopening. In this context, the body may include a lower portion whichdefines an annulus concentric with the opening. The annulus may beconfigured to align with the recess in the upper surface of a blendinglid of the same kind and configuration when two of such blending lidsare stacked one on top of another. Lugs may be provided in the recess,for engagement by the annulus of a blending lid of the same kind andconfiguration when two of such blending lids are stacked one on top ofanother.

The body may have a central portion in the middle of which is theopening and an outer portion concentric with the opening, and a gaparranged between the central portion and the outer portion, when viewedfrom above. In this context, the body may include a lower portion whenviewed from the side, which is configured to locate in the gap betweenthe central portion and the outer portion of a blending lid of the samekind and configuration when two of such blending lids are stacked one ontop of another. Denesting lugs may be provided in the gap, such that thelower portion of a first of the blending lids engages the lugs on asecond of the blending lids, when the first blending lid is stacked ontop of the second blending lid.

The annulus may project downwards so as to extend into a container whensealing fitted onto the container for a blending operation. An outerportion of the annulus may define a wall for abutment with orarrangement in close proximity with an internal surface of a containerwhen sealing fitted onto the container for a blending operation. In thiscontext, the blending element may include at least one blending blade,wherein the annulus projects a distance greater downwardly than thedistance than the at least one blending blade projects from the body.The body may include a rim for fitting over the open end of a containerfor sealing ingredients in the container for a blending operation,wherein the rim defines an outer wall which projects downwardly by adistance which is less than the distance that the blending elementprojects from the body.

The body may have a planar upper portion and the blending element mayinclude one or more blades configured to rest against or adjacent theplanar upper portion of a blending lid of the same kind andconfiguration when two of such blending lids are stacked one on top ofanother.

The lid may be a single-use plastics component for disposal after asingle blending operation.

Further features of the invention appear from the following descriptionof various embodiments of the invention given by way of example and withreference to the drawings, in which:

FIG. 1 is a vertical cross section through one embodiment of the mixingapparatus,

FIG. 2 is a vertical section corresponding to that of FIG. 1 of anotherembodiment,

FIG. 3 is a vertical section corresponding to those of FIGS. 1 and 2 ofa further embodiment of the invention,

FIG. 4 is a perspective view of the underside of a lid for the mixingapparatus,

FIG. 5 is cross section on the line 5-5 in FIG. 4,

FIG. 5A is an enlarged detail of the cross section of FIG. 5,

FIG. 6 is a view corresponding to FIG. 4 showing the blending elementdisassembled from the lid,

FIG. 7 is a view of the lid of FIG. 4 from the opposite side, inperspective,

FIG. 8 is a plan view from beneath of a lid and blender element assemblyof another embodiment of the invention,

FIG. 8A is a section on the line B-B in FIG. 8,

FIG. 9 is a view corresponding to FIG. 8 from the opposite side of theassembly,

FIG. 9A is a section on the line C-C in FIG. 9,

FIG. 10 is a perspective view of the assembly of FIGS. 8-9 showing theblender element assembled,

FIG. 11 is a sectional view of a stack of assemblies of the kind shownin FIGS. 8-10,

FIG. 12 is a scope view of part of a lid,

FIG. 13 is a similar view to FIG. 12 of an alternative arrangement,

FIG. 14 is a scope view, in perspective, of a lid with blending means,

FIG. 15 is a vertical section through blending apparatus, and

FIG. 16 is a vertical section through other blending apparatus.

Referring to the drawings and firstly FIGS. 1-3, there is shown threeversions of mixing apparatus of which each comprises common elementsincluding a container or container base 10, usually in the form of apaper cup tapering inwardly towards the lower end 10A and having towardsthe upper end a rolled lip 10B. Instead of the container 10 being formedof paper, it may be of plastics, for example of injection mouldedplastics.

In use, the container is assembled with a lid 12 with a turned overperipheral edge 13 which is fitted over the lip or rim 10B and carriesassembled therewith a blending element 14 arranged for rotation relativeto the lid 12.

The blending element 14 is rotated by a drive motor 40 having anupwardly directed drive shaft 41 arranged to engage with the blendingelement 14 for driving engagement during the blending operation.

In FIGS. 1-3, the container 10 and assembled blending element 15 withlid 12 are shown inverted in a position in which product within thecontainer is blended. In this position, the container is inverted withthe lid 12 lowermost and the assembly is supported on an annularsupporting member 42 which locates under the outer edge of the lid 12.

The container 10 is supported and seated in a tapered seating or holder43 which is tapered to the outer shape of the container 10 and extendstowards the upper end of the container so that the upper edge of theholder 43 engages under the container lip 10B. This arrangement ofholder 43, shaped seating 42 and the upper edge of the lid 12 ensures ineach case that the seal between the lid and the container is maintainedthrough all stages of the operation of the blending apparatus, includingwhen the container is inverted, and when the blender is operating priorto blending, the container is located in the holder when upright orinclined towards the user.

Usually the holder 43 is initially in an upright or vertically inclinedposition with its wider end uppermost. The container 10 is located inthe holder by dropping the assembled container and lid into the holder.The holder is then inverted to the position shown in which the lid islocated onto the support 42 with the blending element 14 located overthe drive motor 40. A downwards clamping force F is usually applied tothe holder 43 to maintain it in its inverted position ready for ablending operation. The motor 40 is operated and the drive shaft 41engages the blending element 14 through an opening 20 directed outwardsfrom the lid 12. Rotation of the drive 41 causes the blending element 14to rotate within product located within the container 10. This actionblends the product or otherwise mixes it to ensure that it is adequatelymixed or blended within the container.

When the mixing action has taken place for the required length of time,the clamping force F is released, the drive shaft 41 is disengaged fromthe blending element 14 and the cup holder with the container therein isremoved from the support 42, inverted and released from the holder 43and the product within the container is ready for consumption. As thusfar described it is assumed that the contents of the container to beblended are at the temperature and consistency required but, ifnecessary, the contents may be heated or cooled prior to the blendingoperation. In the case of product which needs to be heated, this may beachieved by directing microwave radiation at product within thecontainer prior to or when in situ on the blending apparatus.

It will be seen that the embodiments of FIGS. 1, 2 and 3 differ fromeach other primarily in the shape of the lid 12. Thus in the case of theFIG. 1 embodiment, the lid 12 is generally planar lying generally at aright-angle to the central axis of the container. The lid 12 is formedwith a central circular opening 11 defined by downwardly, axiallyprojecting members 13 flanked by a depression 15.

In FIG. 2, the lid 12 is of more complex form, although still having anouter rim 13 and a central opening 11. In FIG. 2, the lid is formed witha part spherical central portion 12A in the middle of which is theopening 11, and the outer edge of the spherical portion 12A is turnedthrough approximately 180 degrees to form an outer portion 12B inalignment with and closely adjacent the inner walls of the container 10towards the upper edge thereof. The semi-spherical portion 12A, as shownhas a tangential portion 12C and the transition between the portions 12Cand 12B is through right-angle bends at 12D. Alternatively, the bends12D may be replaced by a curvilinear transition.

It will be seen that the portion 12D is below the level of the upper endof the container and that the semi-spherical portion 12A projects abovethe upper edge of the container and the portion 12A may provide atransparent region through which the internal part of the container maybe viewed. It will also be noted that the region in which the blendingelement 14 is operated, when in the inverted position, as shown, is apartial sphere which assists in ensuring an efficient blending operationof product in the container. The edge of the container opening islocated between portions 12B and 13 of the lid which together define acircumferential slot, the radially inner side of which extends along theinner wall of the container and in contact therewith.

The arrangement of FIG. 3 shows a further alternative form of lid 12,somewhat similar to the lid 12 of FIG. 2 but in which the partsemi-spherical portion 12A is of reduced dimensions so that the upperend of the portion 12A lies substantially level with the upper end ofthe container 10.

The arrangement of FIG. 3 still provides a region in which the blender14 operates which has curved lower surfaces to assist in ensuring anadequate blending action, and the lid may be of transparent material.

The embodiments of FIGS. 2 and 3 are particularly useful in ensuring agood seating of the lid 12 on the container 10 to reduce the possibilityof any leakage or unseating of the lid from the container. One way inwhich this is achieved is for the portion 12B of the lid 12 to extendalong the inner side walls of the upper end of the container givingexcellent sealing qualities and a seating within the container. Thisarrangement also permits a minimal loss of capacity of the container andthis can be overcome by allowing the portion 12A of the lid of thecontainer to project beyond the upper end of the container. The use of acup holder 43 further assists in maintaining a seal between the rim 10Band the lid 12, as shown enlarged in FIGS. 1, 2 and 3. Details of theconstruction of the blender 14 and its associated lid are as describedin relation to the later described embodiments. The extent to which theportion 12B extends into the container can be varied in obtaining anadequate seal. It is preferred that the axial extent of the portion 12Bbe between two and twelve times the depth of the outturned edge 13. Thatis (FIG. 8A) Y=between 2X and 12X.

Referring now to FIGS. 4-7, there is shown a lid 12 and associatedblending element 14 of which similar parts are given the same referencenumerals as in the preceding embodiment. The blending element 14 is ofone piece construction and has a shaft 16 at one end of which is anoutwardly projecting lip 19. At the other end of the shaft 16 is locateda set of blending blades 17 which extend generally radially outwardsfrom the axis.

The shaft 16 is located into a central opening in the lid 12 and aroundthe opening, integral with the lid, are formed arcuate, axially-directedelements 30 which are circumferentially spaced from one another to leavegaps 31. Along each edge of each element 30 there is formed an angledsurface 32 and by provision of the gaps 31 and the angled surfaces 32there is provided means for admitting product within the containerduring blending into the small space between the shaft 16 and theelements 30. By this means the outer surface of the shaft is lubricatedand cooled. This may be necessary since the blending element 14 can berotated at high speed during a blending operation and the shaft 16 is ofrelatively large diameter to provide structural strength to the element14. If product being blended is cold and the blending process is short,such lubrication may not be necessary but lubrication is desirable.Since the container is normally inverted during blending, the blendingelement 14 is immersed in the product and product gains access to theouter surface of the shaft 14. Such product provides a film oflubricant/coolant between the shaft and the element 30.

The shaft 16 is located in the opening by applying axially directedpressure while entering the shaft 16 into the opening and when the lip19 has extended through the opening it locates into a recess at theouter end of the opening to secure the blending element to the lid. Theouter end of the element 14 is formed with an internal depression andshape, as at 20, to enable the drive shaft 41 to enter and fully engagein the opening 20 and drive the blending element 14 during a blendingoperation. The fitting of the shaft 41 in the opening is intended tobring about a strong connection during vigorous blending, which mayinclude blending ice cream.

In the arrangement of FIGS. 4-7, the outer rim 13 of the lid is formedwith slits 34 extending in a generally axial direction from the rim 14towards the top of lid. Such slits 34 assist in locating the lid on thecontainer, the rim being able to be flexed outwards during suchengagement. This may be of particular importance when the container ismade from paper/cardboard. This arrangement also has application whenthe lid is arranged to be fitted to containers which are of slightlydifferent sizes since the flexibility provided by the slits permits thelid to be fitted to different size containers with different size rims.The slits may have a width of some 1 mm and extend to closely adjacentthe inner edge of the rim.

Referring now to the lid assembly of FIGS. 8-10, the same referencenumbers are used for similar parts to those of the previous embodimentsand the lid assembly of FIGS. 8-10 corresponds with that of FIG. 3. Itwill be seen that the blender element is, in this case, formed of twoportions (see in particular FIG. 10) of which one portion 14A is termeda shaft portion and the other portion 14B is termed a blade portion. Theshaft portion 14A is formed with a cylindrical portion 50 which islocated within the opening in the lid defined by the elements 30 whichtogether define bearing surfaces for the blending element 14. At one endof the cylindrical portion 50 is a flange 51 which locates in thedepression 15 formed around the central opening in the lid to therebysecure the blending element at one end thereof.

The portion 14A has a further cylindrical part 52 about which is locatedthe bladed portion 14B of the element in use. Intermediate the portions50 and 52 is provided a portion 54 in which can be seated the bladedportion 14B, when assembled.

In practice, the shaft portion 14A is inserted into the opening in thelid, then from the opposite side of the lid is introduced the bladedportion 14B having a central opening 56 into which is inserted theportion 52. The bladed portion 14B is then pushed over the shaft portion14A to locate the two portions together and the portions are then lockedin position by engaging the inner edge of the opening 56 into a grooveon the portion 54 or a shoulder is provided on the portion 52 over whichthe bladed portion 42 is located to prevent release.

With this arrangement, the two portions 14A and 14B are locked togetheras one, after fitting to the lid 12 and are rotatable relative to thelid within the opening to enable the blending action to be performed.

The outer side of the blending element 14 lies flush with the uppersurface of the lid to provide a neat appearance and, once assembled, thelids and blending elements are nestable together for transportationpurposes, as seen in FIG. 11. To assist in such nesting together, thereis provided lugs 56 against which the portions 12D of the lid arearranged to engage.

In order to provide for easy access to product to be consumed from thecontainer 10, the lid is provided with an opening 58 displaced to oneside of the central axis and having to the upper open side a closuremember 60 which locates into the aperture 58 and is hinged at 62 toenable the closure 60 to be opened and closed according to therequirements of the user.

Referring now to FIG. 11, there is shown a series of lids of the kindillustrated in FIGS. 8-9 which have been nested together aftermanufacture and assembly of the blending elements with the lids. Thesame reference numerals are used in relation to the same parts. It willbe seen that the portions 12D locate in the gap 55 between the portions12C and 12B on an adjacent lid but the portion 12D engages up againstlugs 56 whereby the lids may be readily denested from one another.However it is not essential that the lids be nestable.

The shaft portions 52 of the blending elements locate within the openingat the drive shaft end of the blending element when nested together.Flat portions of the blades 17 of the blending element 14 rest againstthe upper surface of the lids at 12E to assist in enabling the lids tobe nested and denested.

This nesting facility permits the assembled lids and blending elementsto be transported occupying limited volume to a location where the lidsare to be assembled on to the container bases.

Referring now to FIG. 12, there is shown a detailed view of part of alid similar to that of FIGS. 8-9 in which there is formed in the upperside of the lid in the region 12E a pocket 60 depending downwardly intothe container and having opening 62 in the side walls giving access intothe pocket from within the container. Towards the outer side of thepocket 60 is formed an opening 64 giving access into the pocket for aholder 66 which is shaped to be a close fit within the pocket 60,sealing the openings 62 and preventing product from passing out of thepocket 60 to the outside of the container. The holder 66 may contain anyadditive which is required to make to the product during mixing but, inparticular, additives which when contacted by the products within thecontainer will react with the product to create a desired effect. In onearrangement the holder 66 contains material which when contacted by theproduct will carbonate the contents of the container. Such carbonationwill commence when product in the container reaches the opening 62 andenters the holder 66. Reaction between the contents and the carbonationmaterial will set up a carbonation action and this will take place whenthe container is inverted and the contents blended.

Referring now to FIG. 13 an arrangement for a similar purpose to that ofFIG. 12 is provided and the same references are used for similar parts.The arrangement of FIG. 13 primarily differs in that rather than theholder 66 sealing the opening 64, the equivalent holder 67 ofcarbonating product is located in a pocket 60 which is provided with aclosure member 68 which seals the opening 64 at the upper end of thepocket 60.

The closure 68 is pivoted towards the side edge 13 of the lid to bemoved about the pivot between an open condition, as shown, and a closedcondition in which the closure 68 has been pivoted into position overthe opening 64.

The holder 67 of this embodiment may be in the form of a liquidpermeable bag and arranged so that upon contact by the contents of thecontainer, the carbonation material is activated to release carbondioxide into the body of the product.

During use of the container and lid assembly various means can beemployed to ensure good fitting together of the units to avoid leakageand ensure integrity of the assembly.

The fitting of the lid onto the container, as described, is intended toensure this. Moreover rather than having to rely on the operator, theassembly can, at the filling location, or, if filling takes place at thedispensing location, be provided with a clamping mechanism whereby afterthe fitting the lid to the container a pressure plate or other clamp isapplied between the ends of the container and lid until a predeterminedpressure has been reached and this pressure is released. The assemblycan then be inverted and the product is ready to be blended.

After fitting the lid to the container the parts may be united by heatsealing or otherwise.

Referring now to FIG. 14 in which the same reference numbers are givento similar parts of the previous embodiments, an alternative form of lid12 and associated blending means is shown. The lid 12 is similar to thatshown in FIGS. 3, 8 and 9 having an outer rim 13 which fits over theouter edge of a container end and an inner portion 12B which extendsinto the container in contact with or closely adjacent to the inner wallof the container towards its outer edge, the portion 13 and portion 12Bdefining between them a circumferential slot into which the open edge ofthe container is located.

As previously described the container lid has an outwardly convexportion 12A, 12E, which merges with the portion 12B through a turnedover portion 12D.

Centrally of the outwardly convex portion 12A, 12E there is provided anopening O into which is to be located a two part blending means 14. Theshaft part 14A of the blending means 14 has at one end connection meansfor connecting the blending means to the motor drive 41 and has a shaft16 which over its outer surface 50 locates in an opening 56 in theblending element part 14B.

Assembly of the blending means with the lid 12 is by locating shaft part14A through the opening O and through the opening 56 in the part 14B.The surface 50 may be formed with a shoulder to locate with the outerend of the opening 56, or the parts 14A and 14B may be welded togetherafter assembly. The surface 50 locates with the surfaces of the openingO to define a bearing surface which is of relatively small diameter toreduce the potential for the bearing surfaces to overheat.

Also formed in the portion 12E of the lid 12 is an opening 58 which isprovided as an access opening for accessing the contents of thecontainer after blending, for example through a straw.

To be located over the opening 58 during blending is a removable closureor label 58A which is adhesively applied to the lid and is peelabletherefrom when required.

Referring now to FIG. 15 there is shown an alternative arrangement forsupporting an assembly of container 10 and lid 12 during a blendingoperation. The assembled container 10 and lid 12 are located inverted ona support 42 of a housing for the drive motor, as previously described.

Located above the assembly in the blending position is a clampingarrangement 75 including a reciprocal container engagement member 77carried on the lower end of an actuator 78 which is in turn driven by anactuator motor 80 to move up and down towards and away from thecontainer.

The clamping assembly is mounted on a rigid mounting bracket 82 formovement relative thereto through a compression spring 84, the assemblybeing movably supported by a support bolt 86. Movement of the assemblytowards the bracket 82 is against the resistance of the compressionspring 84 and there is also provided a switch 88 which detects movementof the actuator relative to the bracket 82 against the action of thespring 84.

The clamping member 77 is arranged to engage the narrow end of thecontainer 10 to clamp it into position during blending and as thecentral portion 77A which is shaped to match the cross-section of thecontainer to be engaged. Extending around the central area 77A is asafety ring 88 in the form of an annular ring movable relative to themember 77 against spring means 77B. Movement of the ring 88 against thespring means is detected by a switch 79 which, when actuated, stopsmovement of the actuator 78 and actuator motor 80. This arrangementensures that obstructions between the member 77 and the container, suchas an operator's fingers, are detected to stop operation of the clampingarrangement.

In operation of the clamping assembly of FIG. 15 after an assembly ofcontainer and lid has been placed on the support 42, the actuator motoris actuated to cause the clamping member 77 to move downwards intoengagement with the end of the container. A predetermined pressure isapplied to the end of the container to bring about a clamping actionbetween the support 42 and the clamping member 77 and between the lid 12and the container 10. This ensures that the assembly of container andlid is adequately made and support is sufficient during the blendingoperation. Due to the way in which the clamping arrangement is supportedat its upper end there is detected a predetermined pressure on thecontainer through movement relative to the bracket 22 which is detectedby the switch 88 which is irrespective of the size of the container sothe container can have an axial dimension at positions P1 or P2 or atany positions in between. Whatever the size of the container, as soon asthe predetermined clamping pressure has been reached the clampingoperation is complete and there is no further movement of the clampingmember.

It will be appreciated that the blending apparatus can be programmed tooperate according to the size of container used and the contents of thecontainer which may require different blending times. As describedblending apparatus detects the size of container which may alsodetermine the blending duration. However, in addition, the operator canset the blending duration through the operator controls.

Referring now to FIG. 16 there is shown blending apparatus in which thesame reference numbers are, again, given to parts similar to those ofprevious embodiments. The apparatus shown in FIG. 16 includes acontainer 10 and a combined lid 12 and blending means 14 which are ofsimilar form to those shown in FIG. 3 and others of the drawings.

The assembled containers and lid are inverted for a blending operationto the position shown and such inversion can be done manually or bylocating the containers 10 in a holder 43 shaped to the external shapeof the container 10.

The holder 43 may be rotatable about axis A-A from an upright positionin which the container is located into the holder, to an invertedposition in which the blending means 14 is placed in driving engagementwith the drive motor 40 for a blending operation.

The container 10 is generally made of stiff coated paper or card whichis formed with an overlapped portion running in the lengthwise directionof the container. This construction can result in potential problemswith leakage between the lid and the inside wall of the container wherethe overlap occurs.

In order to mitigate any potential leakage there is provided a clampingarrangement whereby the outer surface of the container adjacent the lidhas applied to it inwardly directed clamping forces to assist in sealingthe inner surface of the container against the inwardly directed portionof the lid which locates against said inner surface.

In the illustrated arrangement clamping is by providing an air chamber90 extending around the outside of the container 10 towards its wide endand having a radially inner flexible wall 92 which is arranged tocontact the outer wall of the container so that when the chamber 90 hascompressed gas admitted the wall 92 is caused to extend radially inwardsagainst the container wall. It compresses against the wall to seal thewall against the lid and thereby seal against any leaks.

To assist in the sealing action, there may be inserted into lid over theoutwardly directed circumferential opening extending around the lidportion 12C, a circular abutment member 94. Thus, as the wall 92 filledwith compressed gas to expand inwardly against the container wall,abutment member 94 acts as an abutment to resist such movement and actto assist as a seal.

Compressed gas to the chamber 90 is supplied by a suitable compressorthrough an inlet tube 96 and the tube 96 and chamber 90 are incorporatedinto the holder 43 which holder is directed downwardly to hold theassembly onto the base 42 during blending, as shown by the arrows F.

The chamber 90 is inflated or charged with gas at the commencement ofthe container inversion action and, upon completion of the blending, thetube is deflated so that the container with its blending contents can beremoved from the holder 43.

Air to the chamber 90 may be ducted through tube 98 from an inlet 99lying along the axis A so that the air can be ducted before and duringblending and whilst the holder is rotated.

Instead of using the inflated ring arrangement shown in FIG. 16, amechanical clamping arrangement can be used whereby a metal ring (notshown) in the position of chamber 90 extends around the container and ismoved radially in and out to clamp the container.

Usually clamping around the container will be needed before thecontainer is inverted, during blending, and until the container isupright again.

1. A blending lid for a container, the blending lid comprising a bodyconfigured to be fitted over the open end of a container for sealingingredients within the container, wherein the body has mounted thereonblending means arranged for a high speed rotation, the blending meansextending through an opening in the lid and having, at one end, meansfor connection to a drive motor external to the lid and, at the otherend, a blending element for blending contents of the container when thedrive means is operated, wherein the blending lid is configured forstacking with other blending lids of the same type and configuration,one on top of another, when the blending means is mounted on the body,wherein the body includes an upper portion in which the opening isformed, and wherein the upper portion includes a recess which is annularto said opening.
 2. A blending lid according to claim 1 wherein the bodyincludes a lower portion which defines an annulus concentric with saidopening.
 3. A blending lid according to claim 2 wherein the annulus isconfigured to align with the recess in the upper surface of a blendinglid of the same kind and configuration when two of such blending lidsare stacked one on top of another.
 4. A blending lid according to claim3 wherein lugs are provided in the recess, for engagement by the annulusof a blending lid of the same kind and configuration when two of suchblending lids are stacked one on top of another.
 5. A blending lidaccording to claim 2 wherein the annulus projects downwards so as toextend into a container when sealing fitted onto said container for ablending operation.
 6. A blending lid according to claim 2 wherein anouter portion of said annulus defines a wall for abutment with orarrangement in close proximity with an internal surface of a containerwhen sealing fitted onto said container for a blending operation.
 7. Ablending lid according to claim 6 wherein the blending element includesat least one blending blade, and wherein the annulus projects a distancegreater downwardly than the distance than said at least one blendingblade projects from the body.
 8. A blending element according to claim 6wherein the body includes a rim for fitting over the open end of acontainer for sealing ingredients in the container for a blendingoperation, wherein the rim defines an outer wall which projectsdownwardly by a distance which is less than the distance that theblending element projects from the body.
 9. A blending lid according toclaim 1 wherein the body has a planar upper portion and the blendingelement includes one or more blades configured to rest against oradjacent the planar upper portion of a blending lid of the same kind andconfiguration when two of such blending lids are stacked one on top ofanother.
 10. A blending lid according to claim 1 wherein the lid is asingle-use plastics component for disposal after a single blendingoperation.
 11. A blending lid for a container, the blending lidcomprising a body configured to be fitted over the open end of acontainer for sealing ingredients within the container, wherein the bodyhas mounted thereon blending means arranged for a high speed rotation,the blending means extending through an opening in the lid and having,at one end, means for connection to a drive motor external to the lidand, at the other end, a blending element for blending contents of thecontainer when the drive means is operated, wherein the blending lid isconfigured for stacking with other blending lids of the same type andconfiguration, one on top of another, when the blending means is mountedon the body, wherein the body has a central portion in the middle ofwhich is the opening and an outer portion concentric with said opening,and a gap arranged between the central portion and the outer portion,when viewed from above, wherein the body includes a lower portion whenviewed from the side, which is configured to locate in the gap betweensaid central portion and said outer portion of a blending lid of thesame kind and configuration when two of such blending lids are stackedone on top of another, and denesting lugs are provided in said gap, suchthat the lower portion of a first of said blending lids engages the lugson a second of said blending lids, when said first blending lid isstacked on top of said second blending lid.